Catalytic reduction of unsaturated organic substrates remains a key enabling industrial process that sustains major chemical industries. Fine chemicals production and petroleum upgrading, to name a few, are industries dependent on catalytic reduction of unsaturated organic compounds. Catalytic hydrogenation of unsaturated components of petroleum produces higher quality fuel components. In addition, the hydrogenation and hydrosilylation of a diverse set of unsaturated substrates produce value-added compounds for a wide range of applications. Industrial hydrogenation and hydrosilylation processes are commonly mediated by rare and expensive second- and third-row transition metal catalysts such as platinum, palladium, rhodium and ruthenium. The use of precious transition metals raises barriers to the economics and sustainability of these industrial processes. Hence, there remains a high demand for cost-effective catalyst technologies for hydrogenation and hydrosilylation.
Cheap and abundant first row transition metals are important candidates as economical and less toxic catalyst substitutes. First-row transition metal catalysts have traditionally been believed to possess intrinsically low activity. For example, most nickel-catalyzed hydrogenation reactions are generally much slower than precious metal-catalyzed reaction and require relatively harsh reaction conditions (e.g. 65 atm H2 and 100° C.). However, results of studies on commercial CoMoS2 catalysts can be interpreted to suggest that the active sites of the catalysts may be the cobalt rather than the molybdenum centers. Examples of these studies are detailed in papers such as (1) Duchet, J. C.; van Oers, E. M.; de Beer, V. H. J.; Prins, R. J. Catal. 1983, 80, 386; (2) Vissers, J. P. R.; de Beer, V. H. J.; Prins, R. J. Chem. Soc. Farady Trans. I. 1987, 83, 2145. These results suggest that catalysts containing transition metals such as cobalt may be useful in catalysis. In particular, late first-row transition metals such as Fe, Co and Ni are relatively inexpensive and abundant, making them good candidates for use in hydrogenation reactions.